The Lockheed P-3 Orion has a long history of aerial firefighting in the United States and operated under contract with the US Forest Service for nearly 20 years. It was regarded as the optimal platform for delivering fire suppressants from the air. There are several design features of the P-3 that help it achieve this status:
• Straight Leading Wing Edge - The P-3 has a straight leading wing edge which provides optimal control at low levels and low speeds. Competing turbofan powered airtankers have a swept leading wing edge which is designed for flight at high altitudes and high speeds. This also allows the pilots to approach a drop zone with a nose down attitude so they can easily see the drop target, the lead aircraft, the fire line, and the on-ground firefighters.
• Turboprop Powered – The P-3 has four Rolls Royce Allison T56-A-10W turbine engines producing approximately 4,500 HP per engine. The engines run at a constant RPM and to apply forward or reverse thrust the propeller blade angle is hydraulically manipulated by the pilot. The aircraft is capable of both forward and reverse. This design feature allows the pilot to slow the aircraft in descending terrain fire missions, and provides instantaneous power for immediate climb-out from the drop zone. The engines do not need to “spool up” before altitude is gained, buying the pilot precious seconds in difficult drop zone situations and typical terrain common to aerial firefighting.
• RADSII Retardant Tank – The RADSII tank is rated at 3,000 gallons and complies the USFS Next Generation requirements. It is a gravity fed constant flow tank with 32 drop settings for nearly unlimited line length and pattern. Two forward ram air scoops add air pressure to the top of the payload which helps to force the payload out through the full length longitudinal doors at the bottom of the tank. The advanced computer controlled operation ensure that the payload will exit the tank at the programmed rate regardless of the amount of payload remaining in the tank. It is also capable of carrying fire retardant, water, gel or foam.
• Weight Carrying Capacity – The P-3 can lift 3,000 gallons (27,000 lbs) of payload from all US fire operations bases, and carry a minimum of 6 hours of fuel. This means that the P-3 does not need to be refueled every time it returns to base for more retardant. This unique feature allows for quick turnaround times and safer operation with no “hot loading” and fuel to spare if the pilots require. The P-3 can also land fully loaded saving expensive payloads if required. This design is exactly what is needed for high altitude, hot day, short runway, steep climb out situations common with most fire operations bases.
Airstrike Firefighters, LLC • Email: info@Airstrikefirefighters.com